查找一行給定對象

Question

我有兩個型號

class User < ActiveRecord::Base 
    has_and_belongs_to_many :shops 
end 

class Shop < ActiveRecord::Base 
    has_and_belongs_to_many :users 
end 

我必須找到從加入與用戶對象關聯表users_shops行

任何人都可以請幫我這？

Answer 1

爲UserShop

class UserShop < ActiveRecord::Base 
    belongs_to :user 
    belongs_to :shop 
end 

創建一個新的模型。然後對一些user你可以做

user_shops = UserShop.where(:user_id => user.id) 

，你也可以直接從User

class User < ActiveRecord::Base 
    has_and_belongs_to_many :shops 
    has_many :user_shops 
end 

加關係UserShop和給一些user，你可以做

user_shops = user.user_shops